# US 2019/0170239 A1 · Additively manufactured gearbox with integral heat exchanger > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0170239 A1 - Document ID: US20190170239A1 - Status: Published application - Kind: A1 - Application number: 16/269,623 - Filed: 2019-02-07 - Published: 2019-06-06 - Earliest claimed: 2016-12-12 - Assignees: General Electric Company - Applicants: General Electric Company - Inventors: Gert Johannes van der Merwe; Raymond Floyd Martell - Web page: https://patentgrep.com/patent/US20190170239A1 ## CPC - F02C 7/32: Arrangement, mounting, or driving, of auxiliaries - F16H 57/0417: {Heat exchangers adapted or integrated in the gearing} - B64D 33/08: of power plant cooling systems - F01D 25/12: Cooling - F02C 7/14: of fluids in the plant {, e.g. lubricant or fuel (F02C7/185 takes precedence)} - F16H 57/02: Gearboxes; Mounting gearing therein - F16H 57/0415: {Air cooling or ventilation; Heat exchangers; Thermal insulations} - F28D 7/0041: {the conduits for only one medium being tubes having parts touching each other or tubes assembled in panel form (F28D7/0008, F28D7/0058 take precedence)} - F28D 7/005: {the conduits for only one medium being tubes having bent portions or being assembled from bent tubes or being tubes having a toroidal configuration (F28D7/0008, F28D7/02, F28D7/04, F28D7/06, F28D7/14 take precedence)} - B64D 35/00: Transmitting power from power plants to propellers or rotors; Arrangements of transmissions - F02C 7/224: Heating fuel before feeding to the burner - F05D 2230/30: with deposition of material - F05D 2260/213: by the provision of a heat exchanger within the cooling circuit - F28F 2255/00: Heat exchanger elements made of materials having special features or resulting from particular manufacturing processes - F28F 2255/18: sintered - Y02T 50/60: Efficient propulsion technologies, e.g. for aircraft - F02C: GAS-TURBINE PLANTS; AIR INTAKES FOR JET-PROPULSION PLANTS; CONTROLLING FUEL SUPPLY IN AIR-BREATHING JET-PROPULSION PLANTS (construction of turbines F01D; jet-propulsion plants F02K; construction of compressors or fans F04; generating combustion products of high pressure or high velocity F23R; using gas turbines in compression refrigeration plants F25B11/00) - F16H: GEARING - B64D: EQUIPMENT FOR FITTING IN OR TO AIRCRAFT; FLIGHT SUITS; PARACHUTES; ARRANGEMENT OR MOUNTING OF POWER PLANTS OR PROPULSION TRANSMISSIONS IN AIRCRAFT - F01D: NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES (machines or engines for liquids F03; non-positive displacement pumps F04D) - F28D: HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT (fluid heaters having heat generating means and heat transferring means F24H; furnaces F27; details of heat-exchange apparatus of general) - F05D: INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS - F28F: DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION (water and air traps, air venting F16) - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract A gearbox and a method for additively manufacturing the gearbox are provided. The gearbox includes a housing having an integral heat exchanger additively manufactured within the housing. The heat exchanger includes a plurality of heat exchange passageways for transferring heat between two or more fluids. The heat exchanger is defined at any suitable location or locations within the housing, for example, within voids defined between the walls of the housing and components housed within housing, such as driveshafts, gears, bearings, etc. ## Claims ### Claim 1 A gearbox comprising: a housing comprising a plurality of walls defining an internal chamber; and an additively manufactured heat exchanger formed within the chamber on at least one of the plurality of walls, the heat exchanger comprising a plurality of heat exchange passageways. ### Claim 2 (depends on 1) The gearbox of claim 1, wherein the housing and the heat exchanger are additively manufactured as a single, integral piece. ### Claim 3 (depends on 2) The gearbox of claim 2, wherein the housing is additively manufactured using a first material and the heat exchanger is additively manufactured using a second material, the second material being different from the first material. ### Claim 4 (depends on 1) The gearbox of claim 1, wherein a wall of the heat exchanger has a thickness of less than four millimeters. ### Claim 5 (depends on 1) The gearbox of claim 1, further comprising at least one additively manufactured fluid supply conduit, the fluid supply conduit providing fluid communication between a fluid supply and at least one of the plurality of heat exchange passageways of the heat exchanger. ### Claim 6 (depends on 6) The gearbox of claim 6, wherein the fluid supply is located outside of the housing of the gearbox. ### Claim 7 (depends on 1) The gearbox of claim 1, wherein the plurality of heat exchange passageways comprise a plurality of first heat exchange passageways that are configured for receiving air, fuel, or oil, and a plurality of second heat exchange passageways that are configured for receiving air, fuel, or oil. ### Claim 8 (depends on 7) The gearbox of claim 7, wherein the first heat exchange passageways and the second heat exchange passageways are configured in a cross-flow, counter-flow, or parallel-flow arrangement. ### Claim 9 (depends on 1) The gearbox of claim 1, wherein at least a portion of the heat exchanger is used as a load bearing surface. ### Claim 10 (depends on 1) The gearbox of claim 1, wherein the gearbox is an accessory gearbox or a transfer gearbox of a gas turbine engine. ### Claim 11 A method of forming a gearbox, the method comprising: additively manufacturing a heat exchanger onto at least one wall of a gearbox housing, the heat exchanger comprising a plurality of heat exchange passageways. ### Claim 12 (depends on 11) The method of claim 11, further comprising additively manufacturing the gearbox housing. ### Claim 13 (depends on 11) The method of claim 11, wherein the gearbox housing and the heat exchanger are additively manufactured as a single, integral piece. ### Claim 14 (depends on 11) The method of claim 11, wherein the gearbox housing is additively manufactured using a first material and the heat exchanger is additively manufactured using a second material, the second material being different from the first material. ### Claim 15 (depends on 11) The method of claim 11, wherein a wall of the heat exchanger has a thickness of less than four millimeters. ### Claim 16 (depends on 11) The method of claim 11, further comprising additively manufacturing at least one fluid supply conduit, the fluid supply conduit providing fluid communication between a fluid supply and at least one of the plurality of heat exchange passageways of the heat exchanger, wherein the fluid supply is located outside of the gearbox housing. ### Claim 17 An additively manufactured gearbox comprising: a plurality of chamber walls defining a chamber; one or more gears positioned within the chamber, a plurality of voids being defined between the gears and the chamber walls; and at least one heat exchanger additively manufactured on the chamber walls to fill at least some of the plurality of voids, the heat exchanger comprising a plurality of heat exchanging walls, at least one of the heat exchanging walls having a thickness of less than four millimeters. ### Claim 18 (depends on 17) The additively manufactured gearbox of claim 17, wherein the chamber walls and the heat exchanger are additively manufactured as a single, integral piece. ### Claim 19 (depends on 18) The additively manufactured gearbox of claim 18, wherein the chamber walls are additively manufactured using a first material and the heat exchanger is additively manufactured using a second material, the second material being different from the first material. ### Claim 20 (depends on 17) The additively manufactured gearbox of claim 17, further comprising at least one additively manufactured fluid supply conduit, the fluid supply conduit providing fluid communication between a fluid supply located outside the chamber and the heat exchanger.